A study was made of patients from 55 Chest Clinics in Great Britain who had pulmonary tuberculosis, a persistent cavity 2.5 cm. or more in diameter and whose sputum had been negative for tubercle bacilli for at least a year. Serum specimens were tested for aspergillus precipitins, and the positive results were divided into 'four grades. Chest radiographs including tomograms in those with positive precipitin tests were examined for the presence of appearances compatible with aspergilloma.
Of the 544 patients. 134 (25%) had a positive precipitin test. In 59 patients (11%), radiographs showed typical appearances compatible with an aspergilloma and precipitins were present. A further 19(4%) had less typical but highly suggestive appearances and precipitins. In most of these the precipitin test was strongly positive whilst the result was weaker in those without such radiographic evidence. The maximum prevalence of aspergillus infection occurred in those with cavitated tuberculosis of seven to l1 years duration and it became constant at a somewhat lower level in those with longer-standing disease.
Affected patients had also been given antituberculosis drugs for the longest period, showcd more recent radiographic fluctuation, had larger cavities and cavities with thicker walls, showed more pleural thickening and had more cough and more frequent recent haemoptyses.
Five patients, (1%) without precipitins were found to have radiographs typical of a mycetoma.
A further group of 67 patients with cavities but whose sputum had never revealed tubercle bacilli were also studied. These had a higher rate of aspergillus infection.